will this combo be safe?

[Nathan White 1]

Hello all,

I have put together a parts list but was unsure if the motor would burn out

motor

2200kv
342w
34A max amp
11.1v


ESC

Cont current 40A
peak current 55A
BEC mode linear
BEC. 5v/3A
NiMH. 5-18


Battery

2200mAh
3S
20c - 30c
11.1v 3 cell


Is the discharge to much for the ESC and motor to handle?

Thank you in advance.

[Former Member]

[This posting has been removed]

[Frank Skilbeck]

It all depends on the prop you fit, too large a prop and it will pull to many amps, you've spec'd a 2200 kv motor there which will try and turn at 24,000 rpm (11.1v x 2200kv) on a 3s battery, so you'll need a pretty small prop to keep the amps down or drive the prop via a gearbox. This looks like a heli specific motor designed to work via a large reduction gear.

(Percy beat me to it while I was typing a reply!)

Edited By Frank Skilbeck on 20/01/2015 14:55:13

[Mowerman]

The kv of that motor is as recommended for The Polaris depron model using a 6x6 or 7x4 prop.

As P.V. says ,depends on prop size and type of model. The set-up you list could take the battery near its high limits depending on the prop used.

Also suggest using a watt-meter to check against props to be sure current stays within safe limits of motor/E,S.C. & battery.

[Nathan White 1]

Hello again,

Thank you for the replies, here are some answers to your questions:

Propeller size: I was thinking of using a 5x5 (3S)

Model design: I was thinking of making a low wing speed machine based on the spitfire. Eventually I will be using the motor for a ducted fan for a Vampire of Yak. I am going to make these Foamy's.

Realistically I am more of a design and test sought of guy just trying to push the limits so it's a weight vs needs things for me personally. Even if the components runs relatively warm I see that as a challenge and cooling opportunity.

Thank you again for any information in advance.

[Simon Chaddock]

Nathan

I have to ask but do you have the RC experience to fly such a 'speed machine'?

With modern bits it is quite easy to build an otherwise sound plane but it may be beyond your capabilities to fly it.

Your motor would not really suit a ducted fan if you stay with a 3 cell. A 4000kV motor would be more suitable.

It is worth browsing the Hobby King web site as they give fairly detailed specifications for all their motors and ducted fans. It is not 'gospel' by any means but it gives you an idea sort of stuff required.

If you are seriously into 'experimentation' get a Watt meter. Its the only way you can find out what is actually going on and allows you to stop before something gets overloaded.

[Frank Skilbeck]

Nathan, there you go a run from Drivecalc with a 2200 kv motor, 5 x 5 prop and 3s battery.

[Nathan White 1]

Hi again,

Simon to answer your question, I have some flying experience so I feel it is time to move to a custom build where speed is all the fun. I will hopefully FPV to make the flying a little easier to.

I guess the ducted fan idea will have to wait then until I'm finished with the spitfire build but I will add that to my notes anyhow so thank you for the information. HobbyKing has a fantastic range of components and is where I have been getting the information for the parts I have listed; it's my electronics knowledge that is limited I'm afraid.

Frank that is amazingly useful thank you!

So if I am understanding this correctly the battery you have listed is capable of discharging 77A peak(if 100%) but because of the prop size the motor is limited to only 17.7A which is in safe operation with the ESCs 30A?

Thanks again.

[John Privett]

Nathan, as Simon suggested, get yourself a wattmeter. You can research as much as you like, and run comparisons on Drivecalc and similar programs, but the only way to be sure of the current drawn on a particular setup is to actually measure it.

My Pushycat has a 2200kv motor and I've flown it on both a 5x5 and a 6x4 prop. I get around 8 minutes on a 2200mAh 3S LiPo. So a 5x5 or 6x4 is likely to be about right, but you really should measure the current to be sure that it is within the limits of the motor, the ESC and the battery. Any of those three can be damaged by drawing too much current, the easiest way to do that is to put too big a prop on the motor. So err on the side of a smaller prop if you're uncertain.

[Biggles' Elder Brother - Moderator]

Posted by Nathan White 1 on 20/01/2015 19:53:43:

Hi again,

Simon to answer your question, I have some flying experience so I feel it is time to move to a custom build where speed is all the fun. I will hopefully FPV to make the flying a little easier to.

Trust me Nathan - FPV will not make it easier - just the opposite in fact! Can you give us a better idea of what "some flying experience" is? And have you tried FPV?

BEB

[Stuphedd]

this may be of help .

I use 2200kv motors on my Migs with a 30 amp ESC on 2200mah 3s lipo

6x4 22 amps 14900 rpm

5,5x2 13,5 21000

6x5 25 14000

5x3 14 18200

6x3 18.5 17700

6x4 winsor 18.7 17300

all types of props ,lead to the variations !

cheers

I actually fly it o a 6x3 as the amps lead to a reasonable flight time l

[Nathan White 1]

I am a motorsport student so I already own a multi-meter however I shall take the advice anyway and just test in increments whilst taking measurements. I suppose I should just get both props and see what results I get for my model when complete.

BEB: I have tried FPV once before and really enjoyed it (60FPS really helps) it was placed in the cockpit which made it feel like I was actually on a twitchy plane simulator. my only issue was the limited field of view which can be fixed by a gimball I guess.

I have flown the Trainstar electric trainer (high wing) which was quite nice for learning, didn't like the lack of ailerons; felt cumbersome. I then moved onto the P47D which is a nice little plane, admittedly I did have to dial it down I whole bunch but since I have owned it (2 months) I have been slowly upping the dials. either way I know my limits, afterall I don't want to have to scrap a perfectly good plane.

Pete: awesome info, really helpful. I'm going to add that to my notes, when I get my motor I will run some tests and see how comparative my results are.

[Frank Skilbeck]

Posted by Nathan White 1 on 20/01/2015 19:53:43:

So if I am understanding this correctly the battery you have listed is capable of discharging 77A peak(if 100%) but because of the prop size the motor is limited to only 17.7A which is in safe operation with the ESCs 30A?

It's not "limited" to only 17.7A, but that's the amps predicted to turn that prop at that speed with that motor and the speed is determined by the volts available. But as others have said this is a prediction you should measure the amps to be on the safe side. I must admit I tend to do that with telemetry these days rather than a watt meter, but either is fine.

But the prediction does show that with the combination you've selected that you are well within the ratings of your selected motor and ESC.

[Dave Hopkin]

Posted by Nathan White 1 on 20/01/2015 22:51:22:

I am a motorsport student so I already own a multi-meter however I shall take the advice anyway and just test in increments whilst taking measurements. I suppose I should just get both props and see what results I get for my model when complete.

BEB: I have tried FPV once before and really enjoyed it (60FPS really helps) it was placed in the cockpit which made it feel like I was actually on a twitchy plane simulator. my only issue was the limited field of view which can be fixed by a gimball I guess.

I have flown the Trainstar electric trainer (high wing) which was quite nice for learning, didn't like the lack of ailerons; felt cumbersome. I then moved onto the P47D which is a nice little plane, admittedly I did have to dial it down I whole bunch but since I have owned it (2 months) I have been slowly upping the dials. either way I know my limits, afterall I don't want to have to scrap a perfectly good plane.

Pete: awesome info, really helpful. I'm going to add that to my notes, when I get my motor I will run some tests and see how comparative my results are.

Ermm the Trainstar has ailerons and optional flaps........

**LINK**

[Nathan White 1]

Ermm the Trainstar has ailerons and optional flaps........

**LINK**

oops my bad I thought it was the Trainstar. I can't remember the make, I was given it by a friend a few years ago second hand. looked very similar, closest thing I could find on hobbyking.